


The Right Kind of Pressure

by fuzipenguin



Category: Transformers Generation One
Genre: Established Relationship, M/M, Masturbation, Other, Sticky Sexual Interfacing, Twincest, masturbation with a full waste tank, no excretion of wastes
Language: English
Status: Completed
Published: 2018-03-06
Updated: 2018-03-06
Packaged: 2019-03-27 23:06:46
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,374
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/13891053
Author URL: https://archiveofourown.org/users/fuzipenguin/pseuds/fuzipenguin
Summary: Sideswipe could self-service in all sorts of ways, but he could only do this particular method every now and then





	The Right Kind of Pressure

**Author's Note:**

> Some women enjoy masturbation or sex with a nearly full or very full bladder as it presses against clitoral tissue as added stimulation. I can't actually find a name for that kink/phenomenon, though if anyone knows it, I'd love to add it to my vocabulary!

            Sideswipe stretched as he came out of recharge, all four limbs sprawling. He sighed happily as he wiggled his pedetips against the bottom edge of the bed, luxuriating in the sensation of his plating sliding across the berth cover.

            Not that he didn’t love recharging next to Sunstreaker, but it was nice to have the bed entirely to himself every now and then. In fact, he had their entire quarters to himself for several more hours, due to Sunstreaker picking up an extra shift.

            Normally Sunstreaker wouldn’t do such a thing for anyone, but he was helpless to resist Bluestreak’s pleading optics.

            Sucker.

            Mm… sucking.

            Sideswipe rolled over onto his ventrum, hand slipping underneath him to press against his warming interface panel. What _ever_ could he do with all the free time he had before Sunstreaker came back?

            Sideswipe postulated that he had a healthy libido. Sunstreaker always said Sideswipe was overclocked. The one time Sunstreaker had taken Sideswipe to Medical to complain about his seemingly inexhaustible sex drive, Ratchet had yelled at them to get out of his office and stop wasting his time with stupid slag.

            Regardless, Sideswipe didn’t really have anything better to do until Sunny came back, so self-servicing it was.

            Sideswipe absentmindedly rubbed his face against his pillow, considering what he wanted. Toys? There was that new vibrator they had just gotten. Garishly purple and stubbly, Sideswipe bet the ridges would feel amazing in his valve. Or maybe that spike sleeve. The soft one that felt so good lazily pumping up into.

            Sideswipe’s HUD popped up an alert as his hips continued to grind his interface panel against his palm. He was about to shunt the alert aside when the information actually registered. Once it did, his valve clenched down tightly on nothing as he shivered.

            His waste tank was 92% full.

            He licked his lips and slid his hand up, pressing it against his lower belly, right over his tank. It registered the pressure, prompting his valve to twitch again.

            No wonder he had awoken already a little revved up. There was something about a nearly full tank that pinged his valve to eager readiness. He didn’t know why; Sunstreaker definitely never felt the same way. And while generally not shy, Sideswipe hadn’t felt comfortable asking a medic about it.

            Sideswipe just enjoyed it when he could. He always purposely let his tank fill to near capacity, which meant he emptied it every few weeks versus Sunstreaker who discharged his weekly.

            So. No toys then. But he’d still need some props.

            Sideswipe excitedly rolled to his knees and started gathering all the pillows to himself. Luckily, Sunstreaker was a pillow hedonist. It had only gotten worse when they awoke on Earth and Sunny had started ordering specially-made Cybertronian sized bedding and pillows from nearby cloth manufacturers. Not that Sideswipe minded in the slightest. Yeah, sometimes the berth got a little crowded, but it was much more comfortable than recharging on a metal slab.

            Once he had the pillows arranged the way he wanted, Sideswipe whipped out a large polishing cloth from subspace. He laid it on top of the pillow mound closest to him, then rose up on his knees and flung one leg over. He straddled the bunched up material and slowly sank down, letting his thighs spread.

            Sighing, Sideswipe let his optic shutters flutter shut, enjoying the sensation of the pillow snug against his now hot interface panel. In addition, he had intentionally sat farther back on the pillow, leaving a large amount of it in front of him. His weight at the opposite end made the front portion fluff up. It pressed directly against the plating over his tank when he leaned forward.

            He moaned at the sensation, valve slicking even more. After a few experimental grinds, he finally let his aching cover transform aside. His swollen valve lips made contact with the polishing towel and Sideswipe swiveled his hips a bit, settling more against the pillow.

            He’d done something like this several times before, while riding Sunstreaker’s thigh. And it had always felt good, but the pillows were another thing altogether. They molded to his folds and were just scratchy enough to provide friction to his anterior node.

            Sideswipe pulled the second pile of pillows closer to him. He settled his chest on top, putting his frame into a nice little incline. And then he began to move his lower body.

            He shifted backwards and forwards in slow, purposeful motions. His hips occasionally swiveled in a little figure eight pattern or moved from side to side, but he always returned to the humping motion. He loved the drag of his node over the cloth as he slowly slid forward. Then the quick tug against it as his hips snapped back, only to do it all over again.

            It didn’t take long to soak the polishing cloth, his lubricants welling up and overflowing his valve. He slipped a hand behind him every now and then, two fingers pumping inside his valve for a few strokes. Ultimately though, he derived the most pleasure from his node.

            And the pressure against his waste tank, which seemed wired to the throbbing nub.

            Sideswipe alternated sitting up and lying flat, experimenting with which angles felt the best against his node. He had all morning, so he purposely avoided those positions as much as possible, savoring the push-pull of the fabric against his valve lips instead.

            His imagination always ran wild when he was self-servicing, especially using this method. He liked to pretend there was someone behind him, watching him. Watching his hips shiver and twist, watching the damp spot on the cloth beneath him spread. Watching and wishing that Sideswipe was riding their spike instead. Or maybe their face.

            Sideswipe moaned into the pillow beneath him, his body moving faster at the thought. The last time he and Sunstreaker had sixty-nined, Sideswipe had been on top. His wet valve had made a mess of Sunstreaker’s face as he had rocked over it, Sunstreaker’s nasal ridge rubbing against Sideswipe’s node with the perfect amount of pressure.

            Sunstreaker’s spike had been deep in Sideswipe’s mouth, pre-transfluid trickling down over the back of his glossa and into his intake. Without even thinking about it, Sideswipe brought his left hand up and stuck three of his fingers in his mouth, lips immediately suctioning down around them.

            His cooling fans kicked up another notch and his vents opened to let out the heat building up under his plating. It was getting to the point where edging was becoming torturous. He knew it would make the final overload even better, but he was having trouble staving off the urge to give in.

            He forced himself to slow again, sitting up straighter and taking away some of the pressure against his nub. Sideswipe whined a protest around his fingers, listening to Sunstreaker’s imagined voice in his head telling him to ‘let it build’. Sunstreaker loved to delay Sideswipe’s overloads, loved to watch him squirm and beg for release. But it was always worth it to see the gleam of approval in Sunstreaker’s avid gaze as Sideswipe pushed himself to a fever pitch.

            Sideswipe paused the sway of his hips, leaning back in order to give his wet digits room to slide over his node. They pinched it roughly, his entire frame jerking at the sharp sensation. Then his fingertips soothed over the sting, smearing more of his lubricants around the soft button of metal. He ground against his hand twice before jerking it away, falling forward onto the pillows. He stuck his fingers back into his mouth, glossa laving at the drops of his own lubricant.

            His tank received the most pressure while he was flat like this. Sideswipe made short little thrusts against the pillow between his legs, rocking less against his node and more against his lower abdomen. The pressure was verging on uncomfortable, just the right level to feed into his node and make it throb even harder.

            “Mm… Sunny…” Sideswipe sighed, his fingers of both hands clenching into the berth cover. He knew Sunstreaker would love the view, Sideswipe wantonly humping their little collection of pillows. He’d probably complain later though; even with the polishing cloth covering it, the pillow pressed against Sideswipe's valve was probably damp. The smell would linger for a few days, Sideswipe knew, making Sunstreaker equal parts irritated and aroused.

            Sunstreaker might shove Sideswipe’s face in it the next time he took him from behind. Force him to breath in the musky smell of his own spill. Sideswipe moaned again at the thought, feeling his control beginning to slip.

            His hips began to move faster and Sideswipe decided he’d let it build long enough. Sunstreaker wasn’t here, after all. Sideswipe wanted an overload, and he wanted it _now_.

            Sideswipe started open-mouth panting from the exertion, forehelm pressing against the pillow beneath him. He felt condensation slide down his back, pooling in the dip just above his aft. If Sunstreaker _were_ here, he’d probably lick the trail, maybe even try to suck at the caudal edge of Sideswipe’s valve as it peeped into view on every backstroke.

            “Please…” Sideswipe whispered, imagining the tight grip Sunstreaker would have on Sideswipe’s hips. He whipped his left hand back, fingers spreading across that side of his aft and talon tips digging in. His engine hiccupped at the change in angle and he groaned in frustration as the pressure against his node shifted away.

            He quickly shoved his other hand beneath the pillows between his thighs, pressing upwards. His hips stuttered at the renewed sensation and then starting thrusting urgently. The motions of his pelvis became wild as he chased after his overload. He bore down harder against the pillow, thighs spreading wider to gain firmer contact.

            “Oh, Primus… come _on,”_ Sideswipe muttered. He bit his lip, holding the pillow tighter to himself. Just a little more…

            Then he felt that familiar tingle burst to life in his lower back struts. It quickly moved to his lower abdomen, squeezing across his hips and moving upwards to his spark. His lower back started to arch, all of the pressure centering on his anterior node.

            “Ohhh… nnghh… yeah, yeah… _please_ …” Sideswipe moaned, his frame tightening, tightening, tightening…

            His body suddenly froze, all of his transistors tripping as they hit maximum capacity and overloaded. A low moan trickled up out of his throat as his pelvis tilted down, using his weight to grind his nub onto the pillow in tiny little thrusts.

            Sideswipe abruptly collapsed forward onto the pile of pillows, strutless except for his pelvis. It continued to hump his valve against the soaked cloth in fitful little motions. The bunched up edge of the pillow pressed against his tank and he moaned in satisfaction, shifting backwards and forwards to savor the last bursts of sensation from both areas.

            His entire body felt heavy, warm and loose. These overloads always wiped Sideswipe out, made him blissfully sleepy. He probably would have fallen into recharge right then and there except he felt a gentle touch along the twinbond.

            Seconds later he felt drops of something wet spattering across his lower back. Then firm hands grabbed hold of his waist, lifting him up enough so that a still twitching spike could fully seat itself inside his valve.

            “You’re so hot,” Sunstreaker whispered fiercely into Sideswipe’s audial. He draped himself along Sideswipe’s back and carefully bore Sideswipe back down onto the mound of pillows.

            Sideswipe merely moaned deliriously in reply. His valve was loose and wet and Sunstreaker’s spike fit perfectly, filling up all the empty spaces. Sunstreaker wormed his hand between Sideswipe’s belly and the pillow, palming the plating over Sideswipe’s tank.

            “What are you at?” Sunstreaker murmured, nuzzling the side of Sideswipe’s face. Sideswipe had done this enough times previously for Sunstreaker to know Sideswipe’s tank was probably close to being full.

            Sideswipe let all of his tension bleed out of him now that he was pinned so nicely in place by his twin. “Mmm… 93%,” Sideswipe said drowsily, realizing he’d had another alert pop up. “What’re doin’ back already?”

            “Ratchet finished his inventory early, let me loose,” Sunstreaker replied. “I should have known you’d be playing with yourself without me.”

            “Got a show though, didn’t you?” Sideswipe asked, turning his head to better receive the gentle kisses Sunstreaker was bestowing to Sidewipe’s shoulder.

            “It was definitely a good one,” Sunstreaker said, thrusting once against Sideswipe’s aft. His spike was depressurizing and though normally he’d be doing his best to get Sunstreaker hard again for a second round, Sideswipe was really enjoying this loose-limbed laziness. 

            They could do a second round after a nap. And knowing himself, probably a third and fourth as well.

            Sunstreaker’s fingers pressed upwards again, making Sideswipe arch away from them with a protesting noise. “You want to empty?”

            “Nn. Snuggle,” Sideswipe said, squirming a little. Sunstreaker shifted up enough to let Sideswipe slide to the side. Sunstreaker followed him, spike remaining tucked within Sideswipe’s valve. Pushing clumsily at the pillows, Sideswipe managed to knock the wet one onto the floor and pull a clean one to his chest, cuddling it. He was already halfway to recharge.

            “You’re gonna have to go in like another twenty minutes though,” Sunstreaker pointed out.

            Likely true. But it felt better then. Like little miniature strings tugging at his node, sparking up aftersensations. If he discharged his tank now, he would only feel the relieving of pressure in his abdomen. He wouldn’t be able to feel the waste stream leave the orifice tucked up beneath his node; the little slit usually felt numb post overload.

            Sunstreaker knew that; Sideswipe had explained it to him. But Sunstreaker was probably just as inclined to nap and didn’t want to be woken up again by Sideswipe leaving later. 

            Well, tough.

            “ _Snuggle_ ,” Sideswipe insisted, yanking Sunstreaker’s arm around his waist.

            Sunstreaker sighed. “You’re so weird,” he whispered, but it with fond exasperation.

            “Yeah, but this weirdo’s got a hot aft you love to clang, so shut it,” Sideswipe murmured, pushing said aft back into the cradle of Sunstreaker’s pelvis.

            Sunstreaker sighed again, this time one of defeat. “Good point.”

 

~End


End file.
